The early birds get the returns

April showers: Rows of spinach are ready to go in mid-April.

April showers: Rows of spinach are ready to go in mid-April.

When we started farming in 1988 here in Argyle, New York, we realized that having produce in early May, when the farmers’ markets opened, would be beneficial for many reasons. Farming is our full-time living and, after a long winter with no income, May sales could provide an important boost to our finances. A full display of fresh, May produce would certainly draw the customers to our table and make them loyal buyers for the entire season.

Our early crops

Many different vegetables can benefit from fieldhouse protection. We trialed lettuce, spinach, peppers, tomatoes, beets, swiss chard, basil, and interplanted radishes and scallions. The vegetables we choose to grow early are usually in high demand and are high value crops. They’re also crops we would not be able to have at that time of year if it weren’t for the fieldhouses.

Lettuce is seeded weekly in 200-cell speedling trays in the greenhouse starting in February. Then in March, after they have grown for five weeks in the greenhouse, we transplant 600 lettuce plants each week for three consecutive weeks into one fieldhouse. Planting them 12 inches between rows and eight inches in row gives us a total of 1,800 early, marketable heads of lettuce (12 rows in each house). We sell the lettuce for $1.75 at our retail markets. This one fieldhouse provides us with about $3,100 in the month of May.

“We plant two fieldhouses with spinach over a four-week period…Each fieldhouse produces a crop valued at about $3,200 if we pick leaves only and sell them at $6 per pound at our farmers markets. This extrapolates out to over $100,000 per acre!”
Similarly, we start spinach in the greenhouse in late February in four 200-cell speedling trays. Spinach is seeded every week with three seeds per cell. We generally use the varieties ‘Space’ and ‘Tyee’, but several other varieties are trialed every year. Our experience has shown that ‘Tyee’ works best as a transplant, and ‘Space’ is best for direct seeding in the ground. After the seeds have germinated (five to seven days), we grow them on in the greenhouse for another four weeks. They are then hand-transplanted into fieldhouses with a six-inch spacing between plants and 12 inches between rows.

We plant two fieldhouses with spinach over a four-week period and each crop is ready to start harvesting about four to five weeks after transplanting. We pick the larger leaves only and each planting can be re-picked three to five times about one week apart. Each fieldhouse produces a crop valued at about $3,200 if we pick leaves only and sell them at $6 per pound at our farmers markets. This extrapolates out to over $100,000 per acre! Our timing of transplanting crops into the fieldhouses and out in the fields provides a continuous supply throughout the year.

For several years, we interplanted scallions or radishes between the rows of spinach when the spinach was harvested as a plant (the whole plant was taken). Since the spinach is planted in rows 12 inches on center, the addition of radishes made all rows six inches on center. Those trials were successful for the most part, however, the timing is critical so that the spinach does not overcrowd the radishes.

The lettuce and spinach in the fieldhouses are rowcovered with P-19 Agribon in the early part of the season when temperatures are low. The inside temperatures are monitored daily, and before temperatures reach 70°F inside, the plastic on the side with the boards (that has been secured all winter) is pulled out of the ground and can then be rolled up for ventilation.

Basil is another very lucative crop when extending the season in the spring. Basil is seeded in the greenhouse in early to mid-March and grown in two-inch soil blocks. We then transplant them into a fieldhouse the first week of May and utilize rowcovers to protect them on cold nights. Zip houses over the basil also protect them well and grow them fast inside the fieldhouses. Basil will be ready to cut for fresh bunches soon after transplanting or even at transplanting time, and can be harvested for many months.

Rigging up the water: A simple drip irrigation system makes watering quick and easy–even if you have to use one hose for many houses.

We use a very simple irrigation system for the fieldhouses which consists of drop nozzles mounted on one main overhead plastic pipe attached to the ridgepole. Drip irrigation is another simple and effective system. A hose can be hooked up to a header pipe with irrigation lines running off of it. Any hose system can use quick disconnects (like ours) if many houses are watered with the same hose to save time. Beware: cultivation is more difficult when using drip irrigation. We cultivate the lettuce and spinach crops once with Dutch push-hoes, and side-dress with soybean meal for nitrogen if needed at cultivation.

Winter wonderland

In addition to using these fieldhouses for growing early crops, we also use these structures for various other tasks. The fieldhouses have acted as an overflow/hardening off area for transplants which are started in our greenhouse in the spring (for example: perennials, onions, and greens that are cold tolerant all get transferred to the fieldhouses before going out in the field). During the winter, our ducks and laying hens live in one of the metal-piped fieldhouses.

The metal-hooped fieldhouses not being inhabited by our ducks and hens in the winter months are used for growing. Hardy greens that are planted in early fall, such as spinach, mache, kale, and lettuce, can be harvested all winter.

Around September 1st, we seed lettuce and spinach in the speedling trays and grow them for four weeks in the greenhouse. The plants are then transplanted onto the field around October 1st where we have marked out the location for the fieldhouse. The actual fieldhouse will be constructed over the plants around November 1st. If there is time, the framework of the house can be put up at or before planting time. It is important not to put the plastic on too early since the plants lack cold-tolerance if they are too big going into winter.

The temperature in the fall can vary quite a bit, therefore planting in two successions one-week apart takes away some of the risk. We place wire hoops over the lettuce, then all greens are covered with two layers of rowcover. Only the larger outer leaves are harvested, so the plants can be re-picked all winter. They are usually ready for harvest in December and can be cut when the temperature is above 32°F outside, or if the sun is shining.

I’m dreaming of a green winter: Rows of kale, mache, lettuce and spinach in the winter fieldhouse.

Lettuce doesn’t usually survive the winter depending on the severity of the whether so we plant very little. Mache is a very hardy winter green that can be direct seeded into the fieldhouse area around September 1st, and kale we’ve enjoyed seeded approximately August 1st and put in as a transplant. Aphids can be a problem in late winter, but they usually don’t appear until March when we are tilling everything under to ready the ground for the spring crop.

Winter growing provides our family and friends with good, organic, fresh greens all winter long. Some of our dedicated customers come on a self-serve basis since they enjoy the fresh greens in the dead of winter, and our vegetables in the root cellar (potatoes, carrots, beets, onions, etc.) also add to their selection.

But winter is an important family time for us and a time to rest, so we do not push to sell a lot of produce over the winter. The winter sales we do have provide us with a modest income, and if we ever needed more income, we certainly know how to make a thriving business of winter growing. In addition to providing winter food, the fieldhouses force us to get a jump on the early spring growing. With the structures up before the snow, the ground is ready to plant in March for the new spring crops.

The reward

“Even growing those less cold-hardy crops, in addition to our usual line-up, shows us great returns. One year we grew lettuce and then interplanted tomatoes; those two crops grossed $5,300.”
These fieldhouses have given us a great return over the years, especially since the structures are used over and over again. They are usually unheated except when planted to crops such as tomatoes and peppers. We have been known to use a portable, propane-fired heater when the temperature drops below 40°F. Even growing those less cold-hardy crops, in addition to our usual line-up, shows us great returns. One year we grew lettuce and then interplanted tomatoes; those two crops grossed $5,300. (Note: If tomatoes are grown in either type fieldhouse, some means to get adequate pollination must be used, such as rolling up the plastic on both sides or hand pollinating.)

Season extension on our farm has been a very lucrative addition that we will continue to improve upon and experiment with. However, all this time and energy spent on season extension would not be worthwhile if we didn’t know the cost/benefit of these systems. We utilize simple but critical record-keeping to determine what crops give us the biggest and fastest return in these fieldhouses. All this leads to a great diverse supply of produce for May and November, happy customers and higher profits.

By Paul and Sandy Arnold, Argyle, New York,



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